http://www.scriptlogic.com/kixtart UDF: WeekDaysDiff()

FOR $i = 1 TO 8
  $tDt=Flip_SerDate(@DATE)
  $sDt=Flip_SerDate($tDt)
  $eDt=Flip_SerDate($tDt+$i)
  'Elapsed week days $sDt to $eDt: ' + WeekDaysDiff($sDt,$eDt) ?
  'Elapsed week days $sDt + $i: ' + WeekDaysDiff($sDt,$i) ?
  $eDt=Flip_SerDate($tDt-$i)
  'Elapsed week days $sDt to $eDt: ' + WeekDaysDiff($sDt,$eDt) ?
  'Elapsed week days $sDt - $i: ' + WeekDaysDiff($sDt,-$i) ? ?
NEXT

; Returns at console

;Elapsed week days 2002/06/11 to 2002/06/12: 1
;Elapsed week days 2002/06/11 + 1: 1
;Elapsed week days 2002/06/11 to 2002/06/10: 1
;Elapsed week days 2002/06/11 - 1: 1

;Elapsed week days 2002/06/11 to 2002/06/13: 2
;Elapsed week days 2002/06/11 + 2: 2
;Elapsed week days 2002/06/11 to 2002/06/09: 1
;Elapsed week days 2002/06/11 - 2: 1

;Elapsed week days 2002/06/11 to 2002/06/14: 3
;Elapsed week days 2002/06/11 + 3: 3
;Elapsed week days 2002/06/11 to 2002/06/08: 1
;Elapsed week days 2002/06/11 - 3: 1

;Elapsed week days 2002/06/11 to 2002/06/15: 3
;Elapsed week days 2002/06/11 + 4: 3
;Elapsed week days 2002/06/11 to 2002/06/07: 2
;Elapsed week days 2002/06/11 - 4: 2

;Elapsed week days 2002/06/11 to 2002/06/16: 3
;Elapsed week days 2002/06/11 + 5: 3
;Elapsed week days 2002/06/11 to 2002/06/06: 3
;Elapsed week days 2002/06/11 - 5: 3

;Elapsed week days 2002/06/11 to 2002/06/17: 4
;Elapsed week days 2002/06/11 + 6: 4
;Elapsed week days 2002/06/11 to 2002/06/05: 4
;Elapsed week days 2002/06/11 - 6: 4

;Elapsed week days 2002/06/11 to 2002/06/18: 5
;Elapsed week days 2002/06/11 + 7: 5
;Elapsed week days 2002/06/11 to 2002/06/04: 5
;Elapsed week days 2002/06/11 - 7: 5

;Elapsed week days 2002/06/11 to 2002/06/19: 6
;Elapsed week days 2002/06/11 + 8: 6
;Elapsed week days 2002/06/11 to 2002/06/03: 6
;Elapsed week days 2002/06/11 - 8: 6

FUNCTION WeekDaysDiff ($sdate, OPTIONAL $vdateordays) ; Returns the integer number of week days (M-F) between two dates ; $sDate is a date strings in the form YYYY/MM/DD. Default is today. ; $vDateOrDays is either a date string in the form YYYY/MM/DD or an integer ; of the number of days to count back (neg. int.) or forward from $sEndDte ; Dependencies: Flip_SerDate() or SerialDate() and KiXtart 4.1+ ; Note: If a serial date function is added to KiXtart, the iDOW ; calculation may need to be adjusted to get the correct DOW. DIM $idiff, $idate, $istep, $idow, $ictr, $iend IF ($sdate = '') $sdate=@date ENDIF $idate=flip_serdate($sdate) IF InStr($vdateordays,'/') $itmp=flip_serdate($vdateordays) $idiff=$itmp-$idate ELSE $idiff=0+$vdateordays ENDIF $weekdaysdiff=Abs(($idiff/7)*5) ; Account for full weeks $idiff=$idiff MOD 7 ; remainder of days $idow=($idate MOD 7)+7 ; Returns correct DOW (plus 7) for the ref date IF ($idiff < 0) ; Subtracting days $istep=-1 $idow=$idow-1 ; Start at the previous day ELSE $istep=1 $idow=$idow+1 ; Start at the next day ENDIF $ictr=$idow $iend=$idow+$idiff WHILE ($ictr <> $iend) ; Eliminate the weekends IF NOT ($ictr=0 OR $ictr=6 OR $ictr=7 OR $ictr=13 OR $ictr=14 OR $ictr=20 OR $ictr=21) $weekdaysdiff=$weekdaysdiff+1 ENDIF $ictr=$ictr+$istep LOOP IF ($weekdaysdiff < 0) $weekdaysdiff=$weekdaysdiff*-1 ENDIF ENDFUNCTION ; - WeekDaysDiff -

11 June 2002	WeekDaysDiff()
Author	W.M. Hinsch (New Mexico Mark)
Action	Calculate the number of week days (M-F) between two dates.
Syntax	WeekDaysDiff (Date, [DateOrDays])
Parameters	Date (Required / String) Start date in YYYY/MM/DD format. DateOrDays (Optional / Variant) End date (as string in YYYY/MM/DD format) or integer number of days to count back (negative) or forward.
Remarks	I was just looking for an easy way to only count M-F weekdays between two dates. The idea came about because of the way our help desk system included weekend days in date calculations. It was frustrating to the help desk folks to start a problem Friday, finish it Monday, and have it counted as three days to repair. I developed the algorithm in KiXtart with help from the folks at "http://www.kixtart.org".
Returns	Integer number of week days (M-F) between two dates.
Dependencies	KiXtart 4.1+, Flip_SerDate() (SerialDate may be used as well, but the code and examples will have to be appropriately modified)
Examples	FOR $i = 1 TO 8 $tDt=Flip_SerDate(@DATE) $sDt=Flip_SerDate($tDt) $eDt=Flip_SerDate($tDt+$i) 'Elapsed week days $sDt to $eDt: ' + WeekDaysDiff($sDt,$eDt) ? 'Elapsed week days $sDt + $i: ' + WeekDaysDiff($sDt,$i) ? $eDt=Flip_SerDate($tDt-$i) 'Elapsed week days $sDt to $eDt: ' + WeekDaysDiff($sDt,$eDt) ? 'Elapsed week days $sDt - $i: ' + WeekDaysDiff($sDt,-$i) ? ? NEXT ; Returns at console ;Elapsed week days 2002/06/11 to 2002/06/12: 1 ;Elapsed week days 2002/06/11 + 1: 1 ;Elapsed week days 2002/06/11 to 2002/06/10: 1 ;Elapsed week days 2002/06/11 - 1: 1 ;Elapsed week days 2002/06/11 to 2002/06/13: 2 ;Elapsed week days 2002/06/11 + 2: 2 ;Elapsed week days 2002/06/11 to 2002/06/09: 1 ;Elapsed week days 2002/06/11 - 2: 1 ;Elapsed week days 2002/06/11 to 2002/06/14: 3 ;Elapsed week days 2002/06/11 + 3: 3 ;Elapsed week days 2002/06/11 to 2002/06/08: 1 ;Elapsed week days 2002/06/11 - 3: 1 ;Elapsed week days 2002/06/11 to 2002/06/15: 3 ;Elapsed week days 2002/06/11 + 4: 3 ;Elapsed week days 2002/06/11 to 2002/06/07: 2 ;Elapsed week days 2002/06/11 - 4: 2 ;Elapsed week days 2002/06/11 to 2002/06/16: 3 ;Elapsed week days 2002/06/11 + 5: 3 ;Elapsed week days 2002/06/11 to 2002/06/06: 3 ;Elapsed week days 2002/06/11 - 5: 3 ;Elapsed week days 2002/06/11 to 2002/06/17: 4 ;Elapsed week days 2002/06/11 + 6: 4 ;Elapsed week days 2002/06/11 to 2002/06/05: 4 ;Elapsed week days 2002/06/11 - 6: 4 ;Elapsed week days 2002/06/11 to 2002/06/18: 5 ;Elapsed week days 2002/06/11 + 7: 5 ;Elapsed week days 2002/06/11 to 2002/06/04: 5 ;Elapsed week days 2002/06/11 - 7: 5 ;Elapsed week days 2002/06/11 to 2002/06/19: 6 ;Elapsed week days 2002/06/11 + 8: 6 ;Elapsed week days 2002/06/11 to 2002/06/03: 6 ;Elapsed week days 2002/06/11 - 8: 6
Source	FUNCTION WeekDaysDiff ($sdate, OPTIONAL $vdateordays) ; Returns the integer number of week days (M-F) between two dates ; $sDate is a date strings in the form YYYY/MM/DD. Default is today. ; $vDateOrDays is either a date string in the form YYYY/MM/DD or an integer ; of the number of days to count back (neg. int.) or forward from $sEndDte ; Dependencies: Flip_SerDate() or SerialDate() and KiXtart 4.1+ ; Note: If a serial date function is added to KiXtart, the iDOW ; calculation may need to be adjusted to get the correct DOW. DIM $idiff, $idate, $istep, $idow, $ictr, $iend IF ($sdate = '') $sdate=@date ENDIF $idate=flip_serdate($sdate) IF InStr($vdateordays,'/') $itmp=flip_serdate($vdateordays) $idiff=$itmp-$idate ELSE $idiff=0+$vdateordays ENDIF $weekdaysdiff=Abs(($idiff/7)5) ; Account for full weeks $idiff=$idiff MOD 7 ; remainder of days $idow=($idate MOD 7)+7 ; Returns correct DOW (plus 7) for the ref date IF ($idiff < 0) ; Subtracting days $istep=-1 $idow=$idow-1 ; Start at the previous day ELSE $istep=1 $idow=$idow+1 ; Start at the next day ENDIF $ictr=$idow $iend=$idow+$idiff WHILE ($ictr <> $iend) ; Eliminate the weekends IF NOT ($ictr=0 OR $ictr=6 OR $ictr=7 OR $ictr=13 OR $ictr=14 OR $ictr=20 OR $ictr=21) $weekdaysdiff=$weekdaysdiff+1 ENDIF $ictr=$ictr+$istep LOOP IF ($weekdaysdiff < 0) $weekdaysdiff=$weekdaysdiff-1 ENDIF ENDFUNCTION ; - WeekDaysDiff -

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